The present invention relates to a device for guiding a puncture needle for allowing the needle to precisely reach a target site in a subject or a patient (hereinafter referred simply to as xe2x80x9csubjectxe2x80x9d) in accordance with a target determined by image data. The puncturing operation being percutaneously carried out with respect to a pectoral region or an abdominal part of the subject in accordance with a target determined by image data, particularly image data obtained in CT (computerized tomography) scanner and the like.
In the case where a puncturing operation is percutaneously performed with respect to a pectoral region or an abdominal part of a subject in accordance with a target determined by image data obtained in CT (computerized tomography) scanner and the like, an examiner or an operator (hereinafter referred to simply as xe2x80x9cexaminerxe2x80x9d) confirms a target site, decides a puncturing position, a depth, and a direction (a puncturing route) for a puncture needle, and manipulates the puncture needle so as to reach the target site from the surface of the subject body (hereinafter referred optionally to as xe2x80x9csubject""s body surfacexe2x80x9d) while confirming a needlepoint of the puncture needle under its image, besides the puncturing operation must be made while maintaining a parallel state with respect to the cross section of such CT image,
Particularly, the examiner is requested to reproduce the puncturing route determined in the image to perform the puncturing operation. Accordingly, it is an important point from a viewpoint of manipulation to be performed by the examiner how much exact puncturing operation.
In the case where manipulation for a puncturing operation with a needle is practiced clinically without employing any device for guiding such puncture needle, the operation is carried out in such that a position to be punctured in a subject is marked, a needle tube is calibrated as a navigation mark for a depth, CT-photographing is repeated for adjustment of a direction and necessity of puncturing exactly a target, and a needlepoint of the puncture needle is observed by a monitor under its image.
In this case, if it is difficult to capture exactly a target site and to puncture parallel the target site in conformity with a cross section of its image, such events wherein a needle does not reach a target site by a single try occur frequently. In such case, it is necessary for beginning again the puncturing operation. Furthermore, in a monitor observation during a puncturing operation, it is required to repeat photographing for confirming a position of the puncture needle, so that it is desired for an administration wherein an amount of exposure to radiation is reduced with respect to a subject, and for making an arrangement by which significant burden is not given to the subject by reducing a period of time for examination as much as possible.
In order to eliminate the above described disadvantages, devices for guiding puncture needle which are intended to apply to a pectoral region or an abdominal part of a subject have been proposed. They are, for example, a device provided with an angle gauge which is fixed to an examining table; or a device for holding a biopsy needle on a curved arm in a circular arc shape which is employed by fixing to an examining table (Japanese Patent Laid-Open No. 236633/1995); a device for guiding a puncture needle which is provided with a level, a protractor, and a guide plate for the puncture needle and which is employed by floating the same from an examining table on the basis of horizontal plane as its reference (Japanese Patent Laid-Open No, 127036/1987); or a device wherein a number of strings which are not allowed X-rays to pass through them are stretched in two stages with respect to a tetragonal cylindrical body and which has a holding section for a puncture needle being photographed together with a target site, whereby the target site can be determined on the extension from two points in a visible section (Japanese Patent Laid-Open No. 238248/1996); and the like.
When a puncture needle is pierced in accordance with each guiding mechanism by utilizing any of these devices for guiding puncture needle, it becomes possible to allow a needlepoint of the puncture needle to reach a target in conformity with a cross-sectional plane of its image at a certain degree, and further it is expected to reduce the number of times for photographing.
Recently, an image; can be observed real time while scanning continually sections with development of CT apparatus. Hence, manipulation can be performed while confirming always a needlepoint under CT transmission. Accordingly, it becomes possible to perform relatively easy a puncturing operation with high precision.
On the other hand however, since X-rays are continuously exposed in a gantry of a continuous CT scanning apparatus, an amount of exposure to X-rays is significantly restricted by a law as to prevention of radiation damage due to radioactive isotopes and relative laws and ordinances in practical manipulation, Moreover, an administration for direct exposure to radiation upon an examiner during his (or her) manipulation becomes a problem.
In order to solve such exposure problems, a device wherein a major detection needle is connected perpendicularly to a rod serving as a handle; and a needle holder composed of a needle holding section and a handle disposed in parallel to the needle holding section wherein the handle is disposed away 4 to 7 cm from the holding section (Japanese Patent Laid-Open No.140716/1997) have been proposed. When these devices are used, it is possible to avoid direct exposure to radiation with respect to fingertips of an examiner.
However, according to conventional devices for guiding puncture needle, in a device of the type which is fixed to an examining table, since a guiding device must be fixed to an exact position after deciding a target for puncturing with a needle, there is a problem of requiring a much time before starting a puncturing operation because of such troublesome fixing operation Particularly, if there is a movement of a subject""s body during examiner""s manipulation, the puncture needle deviates from the target site, and further there is a danger of bending or breaking of the puncture needle in the worst case, because the guiding device is fixed to the examining table. Furthermore, the circular arc-shaped device to be attached to an examining table involves also the same problems as that contained in the above described guiding device. In addition, the device contains a problem of large number of parts, and a problem of a complicated structure.
In a device provided with a level or the like, since it is used in a floating state from an examining table, problems relating to fixation of the above described devices are eliminated. However, it is required that the device must be kept horizontal during examiner""s manipulation by the use of the level, In a practical use, there is clinically a rare case where a subject""s body surface on which the device is to be placed is maintained in a horizontal state. Accordingly, the device must be kept horizontal by an assistant or the like, but it is difficult to maintain a horizontal state during examiner""s manipulation.
In a tetragonally cylindrical device provided with strings which are not allowed X-ray to pass through the same, such a problem wherein the device must be kept horizontal during manipulation by an assistant or the like is eliminated, because the device can be used in such a situation that it has been attached to a subject""s body surface, However, such device involves a complicated structure and the number of parts therefore increases.
Moreover, a device for a needle holder which is practiced under CT vision through according to a real time CT apparatus can prevent exposure to radiation upon an examiner, but a grip section is not directly connected with a needle, Further; since a puncturing operation is performed with holding the grip section by an examiner, subtle feeling appearing in the case where the needlepoint of a needle piercing a subject""s tissue cannot be transmitted to examiner is fingertips, Furthermore, since an introducer or a puncture needle guide is not used, there is a case where the puncture needle curves in piercing a subject""s body, so that an exact puncturing operation becomes difficult. A problem of curved needle is particularly remarkable in case of employing a thin needle; In addition, although a target is captured real time under CT image, it is difficult to allow a needle tube to reach directly a target site along an assumed puncturing route. Thus, there is a problem in that the needle is out of a CT section in some cases, so that the needlepoint cannot be checked on.
On one hand, since the inside of a gantry in CT has a diameter of around 600 mm, a distance extending from the lower end of the gantry to a subject""s cuticle in a puncturing section is short in case of performing a puncturing operation under CT image wherein a conventional guiding device as mentioned above is employed. As a result, there are frequently such a case where a puncture needle is hard to be contained in a space defined in the gantry, because of a length of the puncture needle or the guiding device, and such a case where examiner""s manipulation is difficult, because of a narrowed space for manipulation.
In such a case as described above, a subject must be once transferred to the outside of the gantry in order to puncture the subject""s body with a needle. Moreover, since a needlepoint must be confirmed number of times during manipulation for puncturing operation, the subject is transferred to the inside and the outside of the gantry on all such occasions, so that there is such a problem that the subject is considerably burdened, In such type of a device for guiding a puncture needle as mentioned hereinbefore, there is such a need that in an event where examiner""s manipulation is completed as a result of puncturing exactly a target site in a subject""s body with a needle, and then, separate manipulation follows while leaving a needle tube as it is, the device for guiding a puncture needle forms clinically an obstacle to the separate manipulation in some cases, so that the guiding device is removed from the subject""s body with leaving only the puncture needle, a conventional guiding device could have not coped with such need. Accordingly, such a device for guiding a puncture needle by which only the guiding device can be removed from a subject""s body with leaving a needle tube punctured as it is, whereby examiner""s manipulation can be easily practiced is strongly desired.
Accordingly, an object of the present invention is to provide a device for guiding a puncture needle having a simple structure, composed of small number of parts, being capable of maintaining sufficiently a space in which manipulation for a puncturing operation is performed with a needle, and being easily and positively attached to the surface of a subject""s body by an examiner.
Furthermore, another object of the present invention is to provide a device for guiding a puncture needle by which a percutaneous puncturing operation can be exactly carried out by a needle with respect to a target site in a subject, besides there is no need of dismounting the subject from a gantry during examiner""s manipulation.
Still another object of the present invention is to provide a device for guiding a puncture needle where there is no fear of exposure to x-radiation to an examiner even in a puncturing operation under CT vision, and is removable from the surface of a subject""s body leaving only a puncture needle after having punctured a target site in the subject.
According to the first feature of the invention, a device for guiding a puncture needle in the case where a puncturing operation with the needle is performed percutaneously with respect to a target site in a subject in accordance with a target determined by image data obtained in CT (computerized tomography), comprises: a guide section having an insertion hole for an introducer and the puncture needle and metal plates that create artifacts for indicating a puncture route when radiation is applied,
a pole brace that changes its length along an axial direction standing erect substantially parallel to the guide section and having a leg for securing the device for guiding a puncture needle to a subject""s body surface; and
a beam for connecting the guide section with the pole brace.
According to the second feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein:
the guide section and the pole brace connected by means of the beam in which the guide section has a height equal with that of the pole brace, or the guide section has a lower height than that of the pole brace.
According to the third feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein:
the pole brace is disposed at a position being substantially parallel to the guide section standing in an erect state, or two of the pole braces are disposed at positions apart from the guide section with equal distances, respectively.
According to the fourth feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein:
the leg in the pole grace contains a suction leg having a function of suction disk ability by which the device for guiding a puncture needle can be secured to a subject""s body surface when placed on the objects body.
According to the fifth feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein:
the beam for connecting the guide section with the pole brace contains a connecting section having a function by which the guide section or the pole brace can be rotated at either of an interconnecting section formed by the guide section and the beam, and an interconnecting section formed by the pole brace and the beam.
According to the sixth feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein:
the interconnecting section formed by the guide section and the beam as well as the interconnecting section formed by the pole brace and the beam are provided, respectively, with a fastening function which can prevent tentatively a movement of the rotatable connecting section to fix a position of the guide section,
According to the seventh feature of the invention, a device for guiding a puncture needle as described in the first feature, where in:
the beam for connecting both the guide section and the pole brace is prepared from a moldable plastic material or the like into an integrally molded article.
According to the eighth feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein;
the beam for connecting both the guide section and the pole brace is composed of a molded article made of a plastic material or the like which allows X-ray to pass through the same and does not produce shadow in its image in case of a applying radiation,
According to the ninth feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein:
the guide section containing the insertion hole is provided with a holding mechanism of an openable, holding section or of a detachable holding section along the longitudinal direction of the insertion hole in order that the device for guiding a puncture needle can be removed from the introducer and the puncture needle which have been inserted in the insertion hole.
According to the tenth feature of the invention, a device for guiding a puncture needle as described in the first feature, wherein:
The metal plates are positioned in parallel and opposite each other on the guide section for creating parallel artifacts.